Recently, it seems that my Seagate HDD is either no longer be recognized by mobo's UEFI/BIOS, or is in some sort of conflict with it. Before that happened, I was actually copying files off it until it got stuck at some file. The file was still at 0% even as I had to leave the house, so I shut the computer off in the meantime. When I got back, my PC gets stuck at POST and won't even let me enter BIOS; disconnecting the HDD in question lets me in without any problems. Since I still had some files to get off the drive, I removed it so I can get past POST, then hotplugged it when I got into Win7. Thankfully, it was recognized and I was able to get the rest of my stuff out. However, the drive still causes the rig to get stuck at POST when it's connected. I was hoping someone understands what's happening here exactly, and if there's still something I can do to get the old drive back.

Currently, I'm under the impression that:
- the drive got stuck in a 'busy' state
- the BIOS is only capable of waiting when the drive says it is busy
- Windows, on the other hand, either sets the drive to 'ready' or is equipped to tell it that it's not actually busy yet since it just got plugged into the system

Admittedly, the drive is already on its way out, which is why I was copying files off it in the first place. It's just that I think the whole stuck at POST thing is a separate problem (that might still be fixable), relative to the other problem that caused the drive to get stuck at copying a file (which I assumed was written in a bad sector, and since it wasn't as important as the rest of the stuff I still had to copy, I simply deleted the whole subdirectory in question).

The drive is kinda old (although the IDE drive that preceded this one is definitely older, and besides being inherently slower at loading OS and mobos not having IDE ports anymore, I'd say it's still fine), but I double checked anyway and it's definitely out of warranty. After some reading, I found out that some drives of the same model needed to update the firmware, however the one I have (version ccf2 iirc) isn't one of those, and flashing an Sxxx version firmware update wouldn't have done any good.

Regarding MBR, would I be able to fix it using the Windows boot cd? I don't normally boot off this drive since I just use it to store games. I'd have to hotplug the drive after POST before I can boot anything, so I'll have to see if the boot cd can detect a hotplug.

Hell, I'd flash the firmware with the same version on it if it was provided. I just want to know what sort of problem causes the drive to not get along with the BIOS anymore when it gets disrupted in the middle of copying files from it. At worst, I was just expecting a corrupted file on the destination disk.

Another possibility is that the SATA controller or cable is bad - you can switch to a different port on the motherboard or switch cables (use both a different power and data cable).
What does Seatools say about the drive?SeaTools | Seagate

If it failed anything in there, don't waste your time trying to fix it.

__________________"The computer programmer says they should drive the car around the block and see if the tire fixes itself." [src]

Another possibility is that the SATA controller or cable is bad - you can switch to a different port on the motherboard or switch cables (use both a different power and data cable).
What does Seatools say about the drive?SeaTools | Seagate

If it failed anything in there, don't waste your time trying to fix it.

It's definitely not the cables nor the ports, since I was able to get my data off successfully when I hotplugged it.

Some results from Seatools, though I don't know how to interpret them besides the drive is already bad. I assume these are more related to the drive having difficulty copying the file that one time, rather than goofing off with the BIOS at POST.

I have to mention that some of the failed tests automatically ejected the drive, with Windows giving the similar sound it does when you pull a USB device off. In fact, the drive's SMART has been red for a good while until I had the chance to get a replacement, and it only failed this horribly as I was taking care of the situation. It kinda makes sense though, since copying almost all of its content is probably the most demanding task I ever subjected it to do (go figure). To be honest, I'm not as concerned about this particular drive, than I am with the fact that getting interrupted during an operation can cause a drive to not let my system boot. I wanna know how that works so I can do something about it next time, because with my luck, something similar is definitely a possibility.